diffcore-break: fix leaking filespecs when merging broken pairs

When merging file pairs after they have been broken up we queue a new
file pair and discard the broken-up ones. The newly-queued file pair
reuses one filespec of the broken up pairs each, where the respective
other filespec gets discarded. But we only end up freeing the filespec's
data, not the filespec itself, and thus leak memory.

Fix these leaks by using `free_filespec()` instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diffcore-break.c

@@ -266,8 +266,8 @@ static void merge_broken(struct diff_filepair *p,
 	 * in the resulting tree.
 	 */
 	d->one->rename_used++;
-	diff_free_filespec_data(d->two);
-	diff_free_filespec_data(c->one);
+	free_filespec(d->two);
+	free_filespec(c->one);
 	free(d);
 	free(c);
 }

t/t4008-diff-break-rewrite.sh

@@ -21,6 +21,8 @@ With -B, this should be detected as two complete rewrites.
 
 Further, with -B and -M together, these should turn into two renames.
 '
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-diff.sh ;# test-lib chdir's into trash
 

t/t4022-diff-rewrite.sh

@@ -2,6 +2,7 @@
 
 test_description='rewrite diff'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-diff-data.sh
 

t/t4023-diff-rename-typechange.sh

@@ -2,6 +2,7 @@
 
 test_description='typechange rename detection'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 . "$TEST_DIRECTORY"/lib-diff.sh
 

t/t4031-diff-rewrite-binary.sh

@@ -2,6 +2,7 @@
 
 test_description='rewrite diff on binary file'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # We must be large enough to meet the MINIMUM_BREAK_SIZE

t/t7524-commit-summary.sh

@@ -1,6 +1,8 @@
 #!/bin/sh
 
 test_description='git commit summary'
+
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 test_expect_success 'setup' '